GENERATION AND ACCELERATION OF UNIFORMLY-FILLED ELLIPSOIDAL BUNCHES OBTAINED VIA SPACE-CHARGE EXPANSION FROM A SEMICONDUCTOR PHOTOCATHODE

We report on the experimental generation, acceleration and characterization of a uniformly-filled electron bunch obtained via space-charge-driven expansion (so called “blow-out regime”) at the A0 photoinjector of Fermilab. The beam is photoemitted from a Cesium-Telluride semiconductorphotocathodeusing a short (< 200fs) ultraviolet laser pulse. The produced electron bunches are characterized with conventional diagnostics and signature of their ellipsoidal character is observed.